Preparation of Colloidal Dispersions of Graphene Sheets in Organic Solvents by Using Ball Milling

Table 1

Fraction of graphene remaining after centrifugation.

Solvent	Surface tension (mJ m^-2)	Remaining after 4000 r.p.m. of centrifugation
		Concentration (𝜇g/ml)	wt% remaining
NMP	41	88.9	35.56
TMU	34.7	88.28	35.31
DMF	35.2	96.67	38.67
THF	26.4	76.03	30.41
Acetone	23.7	66.6	26.64
Ethanol	22.27	10.32	4.128
Formamide	58.35	3.67	1.468